Greetings Posted January 14, 2006 Report Share Posted January 14, 2006 (edited) well, I'm making a disc coversion for my mod frame, and was wondering if the disc shouldnt be mounted the other way round. damn my english is no good to explain my point so here's a drawing:the point is that in trials, you stop the wheel from going backwards, not fowards. it's as if you were mounting a disc the other way round when riding normally (ie. downhill). that's not good because it causes the disc to collapse. apart from that, forces on brakes in trials are much larger than in any other bike sports i think. opinion? Edited January 14, 2006 by Inur Quote Link to comment Share on other sites More sharing options...
deanie-b Posted January 14, 2006 Report Share Posted January 14, 2006 I think your theory is right, My twisted version of this is:The rotor should travel the same way the wheels going, Otherwise the force from the braking would contort the rotor. Quote Link to comment Share on other sites More sharing options...
Walleee Posted January 14, 2006 Report Share Posted January 14, 2006 Your theory is right, but disc's are made of materials which can withstand the forces you mention. Have you ever heard of many disc's colapsing in the same way? I'd say no, because in practise it doesn't happen. Quote Link to comment Share on other sites More sharing options...
nb88 Posted January 14, 2006 Report Share Posted January 14, 2006 I don't see why trials riders use it the wrong way round - surely the brake will be no different? but the rotor arms will be less strong in the wrong direction Quote Link to comment Share on other sites More sharing options...
fairy elephants Posted January 14, 2006 Report Share Posted January 14, 2006 I never thought about this when i put my rear disk on. its on the same way as my front disk, which is the way hope say it should be... works for me Quote Link to comment Share on other sites More sharing options...
Tomm Posted January 14, 2006 Report Share Posted January 14, 2006 Plenty of people put their discs on the "wrong" way around, it doesn't really make any difference. I never heard of anyone cracking a disc... Quote Link to comment Share on other sites More sharing options...
Phatmike Posted January 14, 2006 Report Share Posted January 14, 2006 I never heard of anyone cracking a disc...I've heard of several! Bigman cracked his Hope Trial rotor in 5 places!Thing to remember in trials is that the forces go forwards as well as backwards, such as when you come up short in a gap (backwards) or just stop normally, so it doesn't matter which way you put it. Quote Link to comment Share on other sites More sharing options...
nb88 Posted January 14, 2006 Report Share Posted January 14, 2006 How does moving the rotor around make any difference to braking force though? the braking surface of the disc is the same either side Quote Link to comment Share on other sites More sharing options...
dave85 Posted January 14, 2006 Report Share Posted January 14, 2006 Turning it round makes the difference between the forces pulling along the spokes of the disc, or pushing along them. Quote Link to comment Share on other sites More sharing options...
Prawny Baby Posted January 14, 2006 Report Share Posted January 14, 2006 I've heard of several! Bigman cracked his Hope Trial rotor in 5 places!Thing to remember in trials is that the forces go forwards as well as backwards, such as when you come up short in a gap (backwards) or just stop normally, so it doesn't matter which way you put it.i think hes cracked 3 of them now mike! Quote Link to comment Share on other sites More sharing options...
Tomm Posted January 14, 2006 Report Share Posted January 14, 2006 I've heard of several! Bigman cracked his Hope Trial rotor in 5 places!Oh hush you I don't think it's anything the average trials rider needs to worry about, anyway. Was Bigman's disc on the wrong way? Quote Link to comment Share on other sites More sharing options...
tank_rider Posted January 14, 2006 Report Share Posted January 14, 2006 Turning it round makes the difference between the forces pulling along the spokes of the disc, or pushing along them.In reality i don't think it makes any difference which way round the disc is. I'm open to suggestions though if anyones got any good theories. Quote Link to comment Share on other sites More sharing options...
Walleee Posted January 14, 2006 Report Share Posted January 14, 2006 Perhaps it's because he's a 'big man' and puts more force on a brake than your average 10-11 stone rider?Its six of one, half a dozen of the other, if its going to break, it'll break regardless of which way you put it because as pointed out, the forces are not all acting in the one direction as is the case with xc bikes or downhill. Quote Link to comment Share on other sites More sharing options...
Greetings Posted January 14, 2006 Author Report Share Posted January 14, 2006 still think that there is more force braking backwards than fowards. if not, there would be no problem in making a reliable disc tab for a trials frame. many companies have had problems and probably gave up, not to release unreliable frames. Quote Link to comment Share on other sites More sharing options...
skandy32 Posted January 14, 2006 Report Share Posted January 14, 2006 Plenty of people put their discs on the "wrong" way around, it doesn't really make any difference. I never heard of anyone cracking a disc...yup seconded! I ran both my mini disc brakes on my jump bike for a year or so on the wrong way round..... never noticed a difference to when i put them on properly!! Quote Link to comment Share on other sites More sharing options...
Greetings Posted January 14, 2006 Author Report Share Posted January 14, 2006 yup seconded! I ran both my mini disc brakes on my jump bike for a year or so on the wrong way round..... never noticed a difference to when i put them on properly!!just OT: did you find the brakes strong enough? were they the trials or just mini? thinking of getting some myself. Quote Link to comment Share on other sites More sharing options...
N.Wood Posted January 14, 2006 Report Share Posted January 14, 2006 just OT: did you find the brakes strong enough? were they the trials or just mini? thinking of getting some myself.I used to run a Hope Mini 165mm on the bakc of my trials bike (now on my jump bike) and i progressed so much when i changed from a Mini to a Magura.Unless you were getting a Mono Trials, I'd stick with Magura/V brakes. Quote Link to comment Share on other sites More sharing options...
nb88 Posted January 15, 2006 Report Share Posted January 15, 2006 Turning it round makes the difference between the forces pulling along the spokes of the disc, or pushing along them.I dont get what you mean... surely, as the brake surface is the same on either side, the rotor will stop with the same force because of the pads...which stops the wheel. so why would it differ if you turn it round? Quote Link to comment Share on other sites More sharing options...
flipkickbs Posted January 15, 2006 Report Share Posted January 15, 2006 If the argument is about which way round, or forces on the disc, then although it would be heavy, why not make an actual full disc, a completely solid circular sheet of metal. That way there would be no weak points, and no possible breakages. BOOO YIP!!!!Ps: Im not sober by a long shot Quote Link to comment Share on other sites More sharing options...
Simpson Posted January 15, 2006 Report Share Posted January 15, 2006 All running my tyres round the wrong way was to pull off all the little nobbly bits!On a disk i dont see what difference it would make on some tyres it says like ----> performane <----- durobulity ??sp?? i trust Hope (or the disk manafacturer) if they would have wanted to let you now a disk gives more power the wrong way round then they wouuld have told you. id say it doesnt make any difference myself Quote Link to comment Share on other sites More sharing options...
Greetings Posted January 15, 2006 Author Report Share Posted January 15, 2006 (edited) i trust Hope (or the disk manafacturer) if they would have wanted to let you now a disk gives more power the wrong way round then they wouuld have told you. id say it doesnt make any difference myselfthey probably would, but putting it the other way round doesn't give you more power, it's just more mechanically sound.EDIT: don't want to start another topic, if the mini are too weak, would an M4 hope be good enough? 20" wheels, 8"/7" disc on the rear? Edited January 15, 2006 by Inur Quote Link to comment Share on other sites More sharing options...
Waynio Posted January 15, 2006 Report Share Posted January 15, 2006 (edited) dont forget discs have come from a XC background????? the wheels only ever go forward and dont really slip backwards as there not jumping up walls like us are they?the theory is good and works BUT in trials if you turn the disc around you may find that it does work better the way to do it is to try it Waynio............................yes the Mono M4 would be way powerful enough with a 180mm rotor there really strong and powerful brakes compared to the standard mini, but if your spending that £££ why not buy a trials disc??? Edited January 15, 2006 by Waynio Quote Link to comment Share on other sites More sharing options...
ogre Posted January 15, 2006 Report Share Posted January 15, 2006 "why not make an actual full disc, a completely solid circular sheet of metal. That way there would be no weak points, and no possible breakages. BOOO YIP!!!!"Wouldn't work because of the heat, the holes in the rim are mean to allow air to flow a bit ~(in theory)~ but they do look prety with holes to a soldi disk would be ugly and heavy(er) Quote Link to comment Share on other sites More sharing options...
Greetings Posted January 15, 2006 Author Report Share Posted January 15, 2006 IMO a full disc could actually be weaker. its like a pipe being stronger than a rod. that's just a guess Quote Link to comment Share on other sites More sharing options...
Tomm Posted January 15, 2006 Report Share Posted January 15, 2006 IMO a full disc could actually be weaker. its like a pipe being stronger than a rod. that's just a guess Pipes are only stronger than a rod for a given weight though. A full disc isn't going to be weaker, but it probably won't be much stronger and it would be a lot heavier. Like I said, breaking discs is not an issue*.*see above Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.